Standard Mechanical InterFace (SMIF) technology is widely used for reticle and wafer management in semiconductor fabrication facilities because of its ability to isolate reticles and wafers from harmful contaminants and protect them from mishandling throughout the manufacturing process. SMIF pods are designed for automated handling, transport, and storage of reticles both within the mask shop and between the mask shop and the semiconductor fabrication facility. Reticles are glass plates that contain a pattern of transparent and opaque areas, while wafers begin as silicon substrates that are ultimately processed into semiconductor chips. The reticles are used in the chip manufacturing process. Contamination control is an important part of the chip manufacturing process, both for reticles and patterned wafers.
A reticle SMIF pod designed to Semiconductor Equipment and Materials International (SEMI) standard SEMI E111-0302 includes three main components: the dome (top or cover), the cassette (bottom) which holds the reticle, and the latchkeys. The cassette attaches to the bottom of the dome to create a seal, and is held in place by four spring-loaded latchkeys. If the latchkeys fail to engage the cassette properly, there is a risk that the cassette will separate from the dome, thus allowing the cassette and reticle to fall to the ground resulting in damage and/or contamination of the reticle.